I'm not sure what you're trying to ask me, sometimes an 'a' can be used to differentiate the subject from the object when both appear next to each other and neither of them is human, but in this case it is the 'personal a', used simply because the object is human, the conjugation of the verb clearly states who the subject of the verb is (yo).

I know that if you leave off the la, then it's obviously being used as the personal a. However, if you do have the direct object pronoun (la), then it could be used as clarification. In this case, it isn't correct to do that though. I looked further and found this link, which says the direct object pronoun and clarification can only be used together if the direct object is another pronoun (ex. a ella).
http://www.spanishdict.com/answers/221373/direct-object-pronouns-clarification

Pruebo is a conjugation of "probar," which does also mean "try," but only in the senses of trying something out/testing it, or of tasting something. To convey the attempting to do something sense of English "try" you need "tratar de" or "intentar."

The redundant pronoun is optional although used a lot in Latin American Spanish. It's only obigatory when the indirect object is a personal pronoun OR if it is not a personal pronoun, but precedes the verb. Me dio el libro a mi. A Paco le dio el libro.

Ella is generally used as a subject pronoun, but can also be the object of a prepostion. So, are you asking if the sentence can be: Yo le trato de ver a ella. Yes, it could be, but one would only use that final "a ella" if you needed clarification for some reason. In normal conversation, it probably wouldn't be needed. After adding this comment I was on a Duolungo Immersion and saw a good phrase for you: Le pregunté a ella por qué lo hace. (I asked her why she does it.) ¡Que bueno!

Confusing indeed Inckwise. It appears that trato can mean 'treat' as well as 'try' which is a little strange as there doesn't seem to be an obvious connection between the two, unless a native speaker wants to advise otherwise.

Spanish Dict is correct. Only when the preposition DE follows tratar does the meaning change! Then, the two words together = to try. Trato de se usar Duolingo cada día. (I try to use Duolingo every day.)